Civil Engineering - Concrete Technology - Discussion

M5 - 1:5:10
M7.5 - 1:4:8
M10- 1:3:6
M15 - 1:2:4
M20 - 1:1.5:3

This is Volume Batching. Also when you convert N/sq.mm to Kg/sqcm, you will get M 20 grade as M200 approx. The conversion factor is like 1 N/mm2 = 9.8 Kg/cm2 or approx 10 kg/cm2.

It is also prescribed in the IS 456 that the design mix has to be carried out for mixes above M20.

1:1:2 shall otherwise be used in M25 grade in case of extreme necessity with the consent from Engineer in Charge.

The grade should be M20 and not M200 and it is not economical to produce a concrete with more cement content than aggregate.

I never read such a quality of concrete in any Indian code and books. If it is possible?

Please prefer me that book.

M20 is 20 N/mm2 and M200 is 200 kg/cm2.

For M20 or M200 grade.

Cement : Sand : Aggregate == 1:1.5:3.

What about M15?

Previously I read M15 was supposed to be 1 : 1 : 2. Somebody, please explain.

How it is possible 4:2:1, means - 4 unit cement, 2 unit sand and 1 unit aggregate?

If strength is increase, then why take aggregate only 1%.

1:1.5:3 is for M20 grade, and is 456-2000 is only M40.

M20 and M200 both are same. Only units are different.

1 unit cement 1.5 unit sand and 3 unit aggregate.